The most important aspect of international football management is creating a happy, settled, harmonious and motivated group of players.

This is a greater factor than ever before in international football, probably due to the increasing wealth, fame and egotism of stars. Football squads have always been comprised of big personalities and varying characters, but in the modern era, they possess -- or believe they possess -- genuine power and influence. They're accustomed to high standards; they're used to getting their own way. They can be, in short, spoiled brats.

That description doesn't apply to the vast majority of footballers, of course, but just one bad apple can tear a squad apart. While this is unquestionably a factor at the club level, too, it's even more important when it comes to international duty. If a player is misbehaving at club level, it's not too much of a problem -- the squad isn't together for a particularly long period each day, with many top-level clubs still effectively training only in the morning. The troublesome player has only a few hours each day to cause disruption.

At the international level, it's a completely different experience. A side that reaches the final will end up being together for at least seven weeks if you include pretournament warm-up matches. The experience is highly intense, a 24/7 situation in which players are put together with colleagues they sometimes barely know in a country they've often never been to. There are strange sleeping patterns, lots of long-distance travel and inevitably some logistical problems along the way.

It's about so much more than 90 minutes, and when you think about a World Cup experience on a broader level, you realise why managers place such a huge importance upon taking players who are of the right character. It's why, for example, French manager Didier Deschamps left Samir Nasri off his squad.

Luiz Felipe Scolari is notable for largely failing as a club manager but finding success at the international level.

This, as much as tactical decision-making, was the reason Vicente del Bosque encountered such success with Spain at World Cup 2010 and Euro 2012. He was also blessed with superb footballers, obviously; the most talented bunch Europe has seen in decades. But if the question is about what del Bosque precisely did to facilitate their success, it's about man management and creating a solid group of players off the pitch. "He knows exactly how to deal with players," Fernando Torres once said. "He's very interested in the players' welfare," Sergio Ramos agreed.

Del Bosque has always been something of a reluctant tactician -- he's not the best "solutions" man. When faced with two well-drilled, energetic sides in the Netherlands and Chile this past fortnight, you couldn't help feeling that he didn't entirely understand how to fix the problem.

In interviews over the past six years, del Bosque has relentlessly referred to the importance of the "group" -- not "group" as in "group of death," but group as in "collection of players." It's not quite the same as referring to the squad, which implies a set of footballers. "Group" implies a set of personalities, a coming together of men.

His selection decisions as Spain manager have often hinted at this. For example, he supposedly omitted Roberto Soldado from his Euro 2012 squad because he wasn't sure about the striker's personality. It's not that Soldado was a troublemaker as such, but he was likely to only be a backup, and therefore del Bosque elected to take the forwards he knew and trusted -- Fernando Torres, Pedro Rodriguez -- even though they were badly out of form at club level.

Pepe Reina has been a consistent part of the squad despite barely playing because he's the ringleader in the dressing room, the joker who puts everyone in a good mood. Victor Valdes is a similar case; those two were consistently chosen ahead of David De Gea despite the fact that the Manchester United goalkeeper was nearly a decade younger and the true future of the Spanish side. It took injuries for him to get ahead of Valdes.

"One of the fundamental issues is the good relationship that exists within the group," del Bosque said back in 2012. "I have been fortunate to have a good group made up of nice people. It is important to reinforce relations between the players -- that was a key part of our success in recent years."

Have you ever heard a club manager talking about the importance of selecting "nice people"?

This concept has continued, and even though Spain's World Cup 2014 campaign hasn't been a success, it would be foolish to dismiss del Bosque's achievements. Even when in negotiations with Diego Costa, convincing him to switch from Brazil to Spain, both understood the importance of "the group."

"One of the things that most comes to my mind is the importance of the group," Costa told Spanish publication AS when discussing his decision to play for Spain. "It's one of the things that are most valued in the dressing room and in a team's performance. I made it clear that what was important was the group. If the group was in agreement and believed that it was the right decision for the good of the group, then I was delighted [to represent Spain]."

Spain have had a disastrous 2014 World Cup but it doesn't ruin Vicente del Bosque's accomplishments.

This focus is also something favoured by Luiz Felipe Scolari, now in his second stint as Brazil manager. He believes that the most important aspect of taking Brazil to the 2002 World Cup was "working the pieces together and building a good off-pitch relationship."

Scolari took a similar approach with Portugal when taking them to the Euro 2004 final, controversially leaving out Vitor Baia, who had just won the European Cup with Porto, because he believed the goalkeeper caused problems in the dressing room. It's also why he deliberately kept a settled, reliable squad together from the Confederations Cup despite the recent struggles of players like Paulinho. Scolari himself is almost like a 24th member of the squad -- a joker, someone who actively encourages the antics of David Luiz and Daniel Alves. He's focused on getting the players relaxed. Focused, but relaxed.

Interestingly, Scolari's methods didn't translate to club football. His only experience with a top-flight European side was in 2008-09 at Chelsea, where he was sacked midway through the season; various reports suggested that Chelsea's players couldn't believe the lack of intensity, the lack of physical preparation and the lack of detail in their tactical plans. It felt more like a holiday camp than a work environment. Scolari, meanwhile, admitted to being perplexed about the intricacies of buying and selling highly paid footballers on long contracts, something he didn't have to worry about at the international level.

Scolari basically failed because he took his international methods to club football, where you're supposed to improve footballers in the long-term and formulate various tactical plans for different situations, and where players are, by and large, out of your control for long periods.

Del Bosque, meanwhile, has managed only two club sides. He had a disappointing half-season in Turkey with Besiktas, where he arrived to much fanfare but couldn't help Besiktas contend in that season's title race. He had achieved success at Real Madrid, of course, winning the European Cup and two league titles during a four-year spell. But that was arguably more akin to managing an international side -- managing various superstar players and big egos. He was sacked shortly before Florentino Perez's Galacticos project got out of hand, despite the fact his style was suited to that unusual challenge.

Both Scolari and del Bosque are, essentially, father figures. Look at a photo of them together and the resemblance is uncanny -- perhaps more "granddad" than "father" these days, in their mid-60s. But this is the type of character footballers respond to over the course of a month rather than a more intense, strategy-driven, disciplinarian manager.

It's difficult to imagine Scolari returning to European club football or del Bosque taking charge of a major Spanish club once again. They simply don't seem the right characters for such jobs, but in international terms, regardless of what's happened (or what will happen) at this World Cup, they're the most successful international managers of this century.